/* Suite chrome — tokens + shared UI for Unit 1b modules.
   Canonical source for §7 tokens. Modules 01–05 may still inline a copy;
   modules 06+ should <link> this file and keep only module-specific CSS inline.
   Do not put module-unique selectors here. */

:root{
  /* base — printed paper, never a screen */
  --paper:#e6e1cf;
  --paper-2:#d8d2bc;
  --paper-3:#c9c2a8;
  --void:#050505;
  --void-2:#0c0c0c;
  --panel:#efe9d4;
  --panel-edge:#1a1810;
  --grid:#cfc8ae;

  /* meaning-bearing spot inks */
  --phosphor:#5c6b28;   /* measured data / spectra / live readouts */
  --ember:#a85a32;      /* energy, ionization, emission */
  --signal:#1a6aa3;     /* structure being revealed (subshells, anomalies) */
  --olive:#7e8c45;
  --olive-deep:#4f5a28;
  --mustard:#c4a35a;    /* the electron — mustard yellow, never neon green */
  --neon:#c4a35a;       /* alias of --mustard / --electron (legacy token name) */

  /* particles */
  --proton:#a85a32;
  --neutron:#7e8c45;
  --electron:#c4a35a;

  /* inverted plate — the black-tee panel */
  --plate:#050505;
  --plate-ink:#e8e6d9;

  /* text */
  --ink:#16140e;
  --ink-soft:#33301f;
  --dim:#55513f;
  --faint:#6f6b59;
  --success:#4f5a28;
  --error:#a85a32;

  /* type */
  --font-display:'Archivo Black',Helvetica,sans-serif;
  --font-body:Barlow,Helvetica,Univers,'Helvetica Neue',sans-serif;
  --font-mono:'IBM Plex Mono',ui-monospace,'SF Mono',Menlo,monospace;

  --label-xs:0.72rem;
  --label-sm:0.78rem;
  --label-md:0.85rem;
  --track-wide:0.13em;
  --track-tight:0.08em;
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}
html{font-size:16px;-webkit-text-size-adjust:100%;}
body{
  background-color:var(--paper);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:1.0625rem;
  min-height:100vh;
  overflow-x:hidden;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  text-rendering:optimizeLegibility;
}

/* Base mono recipe — modules extend this selector list in their local <style> */
.mono-label,
.back-link,.mod-meta,.task-kicker,.hud,.debrief-kicker,.briefing-kicker,#stuckBtn,.btn,.mod-tag,.viewport::before{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-feature-settings:"zero" 1;
}

body::before{
  content:'';
  position:fixed;inset:0;
  z-index:9999;
  pointer-events:none;
  opacity:0.14;
  mix-blend-mode:multiply;
  background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size:256px 256px;
}

.module-wrap{max-width:920px;margin:0 auto;padding:1.35rem 1.35rem 3.5rem;position:relative;z-index:1;}
.top-nav{display:flex;align-items:center;justify-content:space-between;gap:1rem;margin-bottom:1.1rem;flex-wrap:wrap;border-bottom:1px solid var(--ink);padding-bottom:0.7rem;}
.back-link{font-size:var(--label-xs);font-weight:500;letter-spacing:var(--track-tight);text-transform:uppercase;color:var(--dim);text-decoration:none;transition:color 0.2s;}
.back-link:hover{color:var(--olive-deep);}
.mod-meta{font-size:var(--label-xs);font-weight:600;color:var(--ink);letter-spacing:var(--track-wide);text-transform:uppercase;}

.task-kicker,.mod-tag{
  display:flex;align-items:baseline;gap:0.7rem;flex-wrap:wrap;
  font-size:var(--label-xs);font-weight:600;letter-spacing:0.16em;text-transform:uppercase;color:var(--olive-deep);
  margin-bottom:0.7rem;
}
.task-kicker::before,.mod-tag::before{
  content:'';
  width:1.6rem;height:0.28rem;
  background:var(--olive-deep);
  flex:none;
  transform:translateY(-0.12em);
}
h1,.task-title{
  font-family:var(--font-display);
  font-size:clamp(1.9rem,4.7vw,2.75rem);
  font-weight:400;
  letter-spacing:-0.025em;
  line-height:0.98;
  color:var(--ink);
  margin-bottom:0.7rem;
}
.framing{
  font-size:1.15rem;
  font-weight:400;
  line-height:1.5;
  color:var(--ink-soft);
  max-width:none;
  text-wrap:pretty;
  margin-bottom:0.85rem;
}
.student-q{color:var(--signal);font-weight:700;}

.viewport{
  position:relative;
  background:transparent;
  border:3px solid var(--ink);
  border-radius:0;
  padding:0;
  margin:0.35rem 0 0;
  overflow:hidden;
  user-select:none;-webkit-user-select:none;
  box-shadow:none;
}
.viewport::before{
  content:attr(data-fig);
  display:block;
  font-size:var(--label-xs);
  font-weight:600;
  letter-spacing:0.15em;
  text-transform:uppercase;
  color:var(--ink);
  background:transparent;
  padding:0.55rem 1rem 0.42rem;
  border-bottom:2px solid var(--ink);
}
.viewport:not([data-fig])::before{display:none;}

.btn{background:transparent;border:1px solid var(--ink);color:var(--ink);font-size:var(--label-md);letter-spacing:0.09em;text-transform:uppercase;font-weight:600;padding:0.65rem 1.3rem;border-radius:0;cursor:pointer;transition:background 0.15s,color 0.15s;margin-right:0.5rem;margin-top:0.4rem;}
.btn:hover{background:var(--ink);color:var(--paper);}
.btn:focus-visible{outline:2px solid var(--olive-deep);outline-offset:2px;}
.btn.submit{background:var(--ink);border-color:var(--ink);color:var(--paper);}
.btn.submit:hover{background:var(--olive-deep);border-color:var(--olive-deep);}
.btn:disabled{opacity:0.35;cursor:not-allowed;}
.btn:disabled:hover{background:transparent;color:var(--ink);}
.btn.submit:disabled:hover{background:var(--ink);color:var(--paper);}

#stuckBtn{background:none;border:1px solid var(--ink);color:var(--ink);font-size:var(--label-sm);font-weight:600;letter-spacing:0.12em;text-transform:uppercase;padding:0.55rem 1.2rem;border-radius:0;cursor:pointer;transition:background 0.15s,color 0.15s;margin-top:1.1rem;}
#stuckBtn:hover{background:var(--ink);color:var(--paper);}
#stuckBtn:focus-visible{outline:2px solid var(--olive-deep);outline-offset:2px;}
.help-panel{opacity:0;max-height:0;overflow:hidden;transition:opacity 0.3s,max-height 0.3s;border:1px solid transparent;background:var(--plate);border-radius:0;padding:0 1.2rem;margin-top:0.75rem;color:var(--plate-ink);font-size:1.05rem;line-height:1.6;max-width:none;text-wrap:pretty;}
.help-panel.open{opacity:1;max-height:320px;padding:1rem 1.2rem;border-color:var(--neon);}
@media (prefers-reduced-motion: reduce){
  .help-panel{transition:none;}
}

/* Section footer — Back left · Stuck? center · Next/Check right */
.module-footer{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);
  align-items:center;
  column-gap:0.75rem;
  row-gap:0.5rem;
  width:100%;
  margin-top:1.25rem;
  min-height:2.6rem;
}
.module-footer[hidden]{display:none !important;}
.module-footer-back,
.module-footer-help,
.module-footer-fwd{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:0.5rem;
  min-width:0;
}
.module-footer-back{justify-self:start;justify-content:flex-start;}
.module-footer-help{justify-self:center;justify-content:center;}
.module-footer-fwd{justify-self:end;justify-content:flex-end;}
.module-footer .btn,
.module-footer #stuckBtn{margin:0;}
.module-footer #stuckBtn[hidden],
.module-footer .btn[hidden]{display:none !important;}
@media (max-width:520px){
  .module-footer{
    grid-template-columns:1fr 1fr;
    grid-template-areas:
      "back fwd"
      "help help";
  }
  .module-footer-back{grid-area:back;}
  .module-footer-help{grid-area:help;}
  .module-footer-fwd{grid-area:fwd;}
}

.briefing{margin:0 0 0.5rem;padding:0.2rem 0 0;width:100%;}
.briefing[hidden]{display:none;}
.module-wrap:has(#briefing:not([hidden])){max-width:1120px;padding-left:clamp(1.35rem,4vw,2.75rem);padding-right:clamp(1.35rem,4vw,2.75rem);}
.briefing-kicker{
  display:flex;align-items:baseline;gap:0.7rem;flex-wrap:wrap;
  font-size:var(--label-xs);font-weight:600;letter-spacing:0.16em;
  text-transform:uppercase;color:var(--olive-deep);margin-bottom:0.7rem;
}
.briefing-kicker::before{
  content:'';width:1.6rem;height:0.28rem;background:var(--olive-deep);flex:none;
  transform:translateY(-0.12em);
}
.briefing h1{
  font-family:var(--font-display);font-size:clamp(1.85rem,4.5vw,2.55rem);
  font-weight:400;letter-spacing:-0.025em;line-height:1.02;color:var(--ink);
  margin-bottom:0.55rem;
}
.briefing-lead{font-size:1.15rem;line-height:1.55;color:var(--ink-soft);max-width:none;margin:0 0 1.5rem;text-wrap:pretty;}
.briefing-columns{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:1.75rem 2.5rem;
  align-items:start;
}
.briefing-actions{
  display:flex;
  justify-content:flex-end;
  flex-wrap:wrap;
  gap:0.5rem;
  margin-top:1.75rem;
  padding-top:1.25rem;
  border-top:1px solid var(--ink);
}
.briefing .btn.submit{margin-top:0;}
#moduleStage[hidden]{display:none;}

.debrief{margin:0.25rem 0 1.25rem;padding:1.2rem 0 0;border-top:1px solid var(--ink);}
.debrief[hidden]{display:none;}
.briefing h2,
.debrief h2{font-family:var(--font-display);font-size:1.5rem;font-weight:400;letter-spacing:-0.02em;line-height:1.1;color:var(--ink);margin-bottom:0.35rem;}
.debrief-lead{font-size:1.05rem;line-height:1.5;color:var(--dim);max-width:none;margin:0 0 1.15rem;text-wrap:pretty;}
.briefing-block,
.debrief-block{border-left:4px solid var(--olive);padding:0.1rem 0 0.1rem 1.05rem;margin-bottom:1.15rem;}
.briefing-block{margin-bottom:0;}
.briefing-block:last-of-type,
.debrief-block:last-child{margin-bottom:0;}
.briefing-block.cc,
.debrief-block.cc{border-left-color:var(--signal);}
.debrief-kicker{font-size:var(--label-xs);font-weight:600;letter-spacing:0.14em;text-transform:uppercase;color:var(--olive-deep);margin-bottom:0.5rem;}
.briefing-block.cc .debrief-kicker,
.debrief-block.cc .debrief-kicker{color:var(--signal);}
.briefing ul,
.debrief ul{list-style:none;margin:0;padding:0;}
.briefing li,
.debrief li{position:relative;padding-left:1.6rem;margin:0.45rem 0;font-size:1rem;line-height:1.5;color:var(--ink-soft);max-width:none;text-wrap:pretty;}
.briefing li{font-size:1.05rem;line-height:1.55;margin:0.55rem 0;}
.briefing-li li::before{content:'\25B8';position:absolute;left:0;color:var(--olive-deep);}
.debrief-li li::before{content:'\2713';position:absolute;left:0;color:var(--olive-deep);font-weight:700;}
.briefing-li li.elsewhere::before,
.debrief-li li.elsewhere::before{content:'\270E';color:var(--ember);}
.debrief-tag{font-family:var(--font-mono);font-size:var(--label-xs);letter-spacing:0.1em;text-transform:uppercase;color:var(--ember);white-space:nowrap;}
.debrief-revisit{
  display:block;margin:0.35rem 0 0;padding:0;
  border:none;background:none;cursor:pointer;text-align:left;
  font-family:var(--font-mono);font-size:var(--label-sm);font-weight:600;
  letter-spacing:var(--track-tight);text-transform:uppercase;
  color:var(--signal);line-height:1.4;
}
.debrief-revisit:hover{color:var(--olive-deep);text-decoration:underline;}
.debrief-revisit:focus-visible{outline:2px solid var(--olive-deep);outline-offset:2px;}
.briefing-cc li::before,
.debrief-cc li::before{content:'\25B8';position:absolute;left:0;color:var(--signal);}
.briefing-cc .cc-name,
.debrief-cc .cc-name{display:block;font-family:var(--font-mono);font-size:var(--label-xs);font-weight:600;letter-spacing:0.12em;text-transform:uppercase;color:var(--signal);margin-bottom:0.15rem;}
.debrief-block.todo{border-left-color:var(--ember);}
.debrief-block.todo .debrief-kicker{color:var(--ember);}
.debrief-todo{list-style:none;margin:0;padding:0;}
.debrief-todo li{position:static;padding-left:0;margin:0.65rem 0;}
.debrief-todo label{
  display:flex;align-items:flex-start;gap:0.7rem;
  cursor:pointer;font-size:1rem;line-height:1.5;color:var(--ink-soft);
  text-wrap:pretty;
}
.debrief-todo input[type="checkbox"]{
  appearance:none;-webkit-appearance:none;
  flex:0 0 auto;width:1.05rem;height:1.05rem;margin:0.2rem 0 0;
  border:1.5px solid var(--ink);border-radius:0;background:var(--paper);
  cursor:pointer;
}
.debrief-todo input[type="checkbox"]:checked{
  background:var(--olive-deep);border-color:var(--olive-deep);
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'%3E%3Cpath d='M2 6.5 L4.5 9 L10 3' fill='none' stroke='%23e6e1cf' stroke-width='1.8'/%3E%3C/svg%3E");
  background-size:0.75rem 0.75rem;background-position:center;background-repeat:no-repeat;
}
.debrief-todo input[type="checkbox"]:focus-visible{outline:2px solid var(--olive-deep);outline-offset:2px;}
@media(max-width:760px){
  .briefing-columns{grid-template-columns:1fr;gap:1.35rem;}
}
@media print{
  .debrief{break-inside:avoid;border-top-color:#000;}
  .briefing h1,.briefing h2,.briefing li,.debrief h2,.debrief li,.debrief-kicker,.briefing-cc .cc-name,.debrief-cc .cc-name,.debrief-tag{color:#000;}
  #stuckBtn,.module-footer{display:none;}
  body::before{display:none;}
}